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LED Retrofit Year One: What to Check at the 12-Month Visit
One year after a factory LED retrofit, the client has twelve months of energy bills and a general sense of whether the new lighting is working. What they usually do not have is a structured picture of how actual performance compares to what was promised. This post covers what a year-one review should contain, how to read the available numbers, and what the visit does for the maintenance relationship.
How Is a LED Year-One Review Different From Solar?
Solar has a monitoring dashboard. After twelve months, the inverter data or PEA/MEA net-metering export gives you a kilowatt-hour figure to compare against the design projection.
LED has no equivalent. The data for an LED retrofit year-one review comes from four sources you compile manually: energy billing data, lux re-measurement, the driver failure log, and the emergency lighting test record. None of these arrive automatically, which is why the twelve-month visit often becomes an informal check-in.
What Data Do You Need Before You Arrive?
Gather these five items in the week before the meeting:
- Energy billing data for the twelve months before and after the retrofit. Ask the client for both sets. If the factory’s production hours changed significantly, note it before the meeting, not during it.
- The original lux measurement record from handover. This is the baseline for re-measurement. If no baseline was taken at handover, note it as a gap to close at this visit.
- The driver failure log. Every driver replaced under warranty or on a reactive call during the twelve months. Zero is a valid result.
- The emergency lighting test record. Whether the emergency fittings were tested during the year and whether results were recorded.
- The original design specification. Target illuminance per area, installed wattage per zone, and the projected annual energy saving.
How Do You Read the Energy Numbers?
The projected saving was built from two inputs: wattage reduction per fixture and estimated annual operating hours. After twelve months, compare actual consumption against the projection.
An example using hypothetical numbers: a factory replaces 300 high-bay metal halide fixtures (400W each) with 150W LED equivalents. The wattage reduction is 250W per fixture. At 3,500 hours per year, the projected saving is approximately 262,000 kWh.
If the actual saving is lower, check whether the actual operating hours match the design assumption. A line that reduced its shifts runs fewer hours than the design estimated, which is not a system failure. Bring the calculation in writing: does the wattage reduction match the specification, and do the actual hours explain the gap?
What Does Lux Re-Measurement Show?
Industrial LED luminaires are rated to an L80 lumen maintenance figure: at the rated hours, the fixture should still be producing at least 80% of its original output. For a quality fitting rated at 50,000 hours L80, twelve months is about 7% of its rated life. Output should be close to the handover reading.
Re-measuring ten to fifteen locations (chosen to match the original handover measurement points) takes about two hours on a production floor. It answers two questions: is the system still delivering the design illuminance level, and are there specific areas where output has dropped below the baseline?
If a re-measured location comes in 10 to 15% below the handover reading, the most common causes are:
- Dust accumulation. Industrial dust on a reflector can reduce output significantly before anyone notices the difference. Clean and re-measure before drawing any conclusion.
- A failing driver running below rated voltage before it fails completely.
- A replacement fixture with a different specification, installed during a reactive call.
What Is a Normal Driver Failure Rate in Year One?
LED drivers are the most common wear component in an industrial LED fitting. For quality commercial-grade drivers in factory environments, early-life failures in year one typically run below 1.5% of installed units. On a 400-fixture installation, that is six or fewer drivers in the first twelve months.
Higher failure rates warrant a closer look at the driver specification: operating temperature range, humidity exposure, and whether the driver is correctly rated for the environment.
Your driver failure log tells you two things: whether the rate is within spec, and whether failures concentrate in one zone, which points to an environmental or electrical issue rather than a random spread.
Why Emergency Lighting Testing Gets Skipped
Emergency lighting in a factory is typically commissioned once and then not formally tested again until a problem is noticed. Thai electrical standards require periodic functional tests, but the actual test cycle depends on the building’s inspection schedule.
For a contractor who installed the emergency fittings, the year-one visit is the natural point to check whether fittings were tested and recorded in the last twelve months. If not, it can be added to the maintenance scope going forward.
A test on a production floor takes about an hour: isolate each emergency circuit, confirm the fittings energize and hold output for the rated duration, and log the results. Small work, but documented evidence that belongs in the site file.
What the Review Does for the Maintenance Conversation
The twelve-month LED review is the right moment to propose or confirm a maintenance agreement. After twelve months you have something specific: an energy saving figure, a lux re-measurement, a driver failure count, and an emergency test record. The conversation is grounded in what actually happened at that site, not in a generic pitch.
A review that shows six driver failures on a 400-fixture installation, lux levels holding within 5% of the handover baseline, and emergency fittings not tested since commissioning gives you a concrete year-two scope: planned driver replacement, annual lux check, emergency test included. Site-specific, not generic. If the client already has a maintenance agreement, this is the renewal touchpoint. If they do not, it is the first time you can discuss one with real numbers on the table.
FAQ
What if the energy saving doesn’t match the projection?
Check the hours calculation first. If actual operating hours were lower than the design assumption, the saving will be lower even if the system is working correctly. If hours match and the saving is still short, check whether any fixtures were replaced with non-specification units.
What if lux re-measurement comes in below the handover baseline?
Clean the luminaires in that zone first and re-measure. Industrial dust can reduce output by 10 to 20% before anyone notices on the floor. If the reading is still low after cleaning, check the driver on those fixtures.
Does the year-one visit have to happen at exactly twelve months?
No. Eleven to thirteen months is the practical range. The goal is a review before the standard LED driver warranty ends and while the installation workmanship warranty is still live, so anything identified can be resolved without a cost dispute.
Scheduled before you need it, a LED retrofit year-one review turns the twelve-month mark from a moment of potential complaint into a structured handover of evidence. If you want to understand how Field Operation System organises the site records and visit logs that make this kind of review straightforward, the details are on the program page.